It is known that food articles may be readily preserved by vacuum storing them in a gasless environment. Likewise, it has been realized that compressible articles or materials may be subjected to a vacuum sealed environment to achieve space saving results. The inventor of the instant invention holds several patents relating to the vacuum packaging technologies. U.S. Pat. Nos. 6,581,253 and 5,142,970, incorporated herein by reference thereto, discloses fluid-tight containers and apparatuses for storing contents of a container in a vacuum sealed environment.
For years many inventors have pursued various techniques for evacuating gases from a container to provide a gasless storage environment. Some of these techniques include using a container that comprises a zipper seal consisting of two strips that are manually forced together along their lengths, such as is disclosed in U.S. Pat. No. 6,059,457. In this instance, a first strip includes a rib extending from a surface thereof. The second strip, opposite the first, comprises at least two ribs extending from a surface thereof. These two ribs are offset from the first such that the rib of the first strip may be forced between the offset ribs to seal an opening in the bag. Air or other gases may be evacuated from the bag via a second opening. The use of this type of seal may not adequately prevent leakage of gases back into the bag after a vacuum source is connected to the bag. The vacuum source creates a negative pressure which tends to pull downward on the seal created by the strips. Thus, the ribs are pulled apart which allows the seal to be broken thereby allowing gas to reenter the bag. While other differences are evident between the instant invention and those details disclosed in U.S. Pat. No. 6,059,457, the use of atmospheric or differential pressures to aid in sealing the closure is unique and new to prior art.
The present invention overcomes the deficiencies of the prior art in that both atmospheric pressure and negative pressure attributable to a vacuum source exert forces in a normal to the surfaces of a seal that seals an opening. Therefore, a more secure seal is realized that does not suffer from the inadequacies of the prior art by utilizing atmospheric and differential pressures to aid in the sealing of the opening.